/*
 * contrib/btree_gist/btree_float4.c
 */
#include "postgres.h"

#include "btree_gist.h"
#include "btree_utils_num.h"

typedef struct float4key
{
    float4        lower;
    float4        upper;
} float4KEY;

/*
** float4 ops
*/
PG_FUNCTION_INFO_V1(gbt_float4_compress);
PG_FUNCTION_INFO_V1(gbt_float4_fetch);
PG_FUNCTION_INFO_V1(gbt_float4_union);
PG_FUNCTION_INFO_V1(gbt_float4_picksplit);
PG_FUNCTION_INFO_V1(gbt_float4_consistent);
PG_FUNCTION_INFO_V1(gbt_float4_distance);
PG_FUNCTION_INFO_V1(gbt_float4_penalty);
PG_FUNCTION_INFO_V1(gbt_float4_same);

static bool
gbt_float4gt(const void *a, const void *b, FmgrInfo *flinfo)
{
    return (*((const float4 *) a) > *((const float4 *) b));
}
static bool
gbt_float4ge(const void *a, const void *b, FmgrInfo *flinfo)
{
    return (*((const float4 *) a) >= *((const float4 *) b));
}
static bool
gbt_float4eq(const void *a, const void *b, FmgrInfo *flinfo)
{
    return (*((const float4 *) a) == *((const float4 *) b));
}
static bool
gbt_float4le(const void *a, const void *b, FmgrInfo *flinfo)
{
    return (*((const float4 *) a) <= *((const float4 *) b));
}
static bool
gbt_float4lt(const void *a, const void *b, FmgrInfo *flinfo)
{
    return (*((const float4 *) a) < *((const float4 *) b));
}

static int
gbt_float4key_cmp(const void *a, const void *b, FmgrInfo *flinfo)
{
    float4KEY  *ia = (float4KEY *) (((const Nsrt *) a)->t);
    float4KEY  *ib = (float4KEY *) (((const Nsrt *) b)->t);

    if (ia->lower == ib->lower)
    {
        if (ia->upper == ib->upper)
            return 0;

        return (ia->upper > ib->upper) ? 1 : -1;
    }

    return (ia->lower > ib->lower) ? 1 : -1;
}

static float8
gbt_float4_dist(const void *a, const void *b, FmgrInfo *flinfo)
{
    return GET_FLOAT_DISTANCE(float4, a, b);
}


static const gbtree_ninfo tinfo =
{
    gbt_t_float4,
    sizeof(float4),
    8,                            /* sizeof(gbtreekey8) */
    gbt_float4gt,
    gbt_float4ge,
    gbt_float4eq,
    gbt_float4le,
    gbt_float4lt,
    gbt_float4key_cmp,
    gbt_float4_dist
};


PG_FUNCTION_INFO_V1(float4_dist);
Datum
float4_dist(PG_FUNCTION_ARGS)
{
    float4        a = PG_GETARG_FLOAT4(0);
    float4        b = PG_GETARG_FLOAT4(1);
    float4        r;

    r = a - b;
    CHECKFLOATVAL(r, isinf(a) || isinf(b), true);

    PG_RETURN_FLOAT4(Abs(r));
}


/**************************************************
 * float4 ops
 **************************************************/


Datum
gbt_float4_compress(PG_FUNCTION_ARGS)
{
    GISTENTRY  *entry = (GISTENTRY *) PG_GETARG_POINTER(0);

    PG_RETURN_POINTER(gbt_num_compress(entry, &tinfo));
}

Datum
gbt_float4_fetch(PG_FUNCTION_ARGS)
{
    GISTENTRY  *entry = (GISTENTRY *) PG_GETARG_POINTER(0);

    PG_RETURN_POINTER(gbt_num_fetch(entry, &tinfo));
}

Datum
gbt_float4_consistent(PG_FUNCTION_ARGS)
{
    GISTENTRY  *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
    float4        query = PG_GETARG_FLOAT4(1);
    StrategyNumber strategy = (StrategyNumber) PG_GETARG_UINT16(2);

    /* Oid        subtype = PG_GETARG_OID(3); */
    bool       *recheck = (bool *) PG_GETARG_POINTER(4);
    float4KEY  *kkk = (float4KEY *) DatumGetPointer(entry->key);
    GBT_NUMKEY_R key;

    /* All cases served by this function are exact */
    *recheck = false;

    key.lower = (GBT_NUMKEY *) &kkk->lower;
    key.upper = (GBT_NUMKEY *) &kkk->upper;

    PG_RETURN_BOOL(
                   gbt_num_consistent(&key, (void *) &query, &strategy, GIST_LEAF(entry), &tinfo, fcinfo->flinfo)
        );
}


Datum
gbt_float4_distance(PG_FUNCTION_ARGS)
{
    GISTENTRY  *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
    float4        query = PG_GETARG_FLOAT4(1);

    /* Oid        subtype = PG_GETARG_OID(3); */
    float4KEY  *kkk = (float4KEY *) DatumGetPointer(entry->key);
    GBT_NUMKEY_R key;

    key.lower = (GBT_NUMKEY *) &kkk->lower;
    key.upper = (GBT_NUMKEY *) &kkk->upper;

    PG_RETURN_FLOAT8(
                     gbt_num_distance(&key, (void *) &query, GIST_LEAF(entry), &tinfo, fcinfo->flinfo)
        );
}


Datum
gbt_float4_union(PG_FUNCTION_ARGS)
{
    GistEntryVector *entryvec = (GistEntryVector *) PG_GETARG_POINTER(0);
    void       *out = palloc(sizeof(float4KEY));

    *(int *) PG_GETARG_POINTER(1) = sizeof(float4KEY);
    PG_RETURN_POINTER(gbt_num_union((void *) out, entryvec, &tinfo, fcinfo->flinfo));
}


Datum
gbt_float4_penalty(PG_FUNCTION_ARGS)
{
    float4KEY  *origentry = (float4KEY *) DatumGetPointer(((GISTENTRY *) PG_GETARG_POINTER(0))->key);
    float4KEY  *newentry = (float4KEY *) DatumGetPointer(((GISTENTRY *) PG_GETARG_POINTER(1))->key);
    float       *result = (float *) PG_GETARG_POINTER(2);

    penalty_num(result, origentry->lower, origentry->upper, newentry->lower, newentry->upper);

    PG_RETURN_POINTER(result);

}

Datum
gbt_float4_picksplit(PG_FUNCTION_ARGS)
{
    PG_RETURN_POINTER(gbt_num_picksplit(
                                        (GistEntryVector *) PG_GETARG_POINTER(0),
                                        (GIST_SPLITVEC *) PG_GETARG_POINTER(1),
                                        &tinfo, fcinfo->flinfo
                                        ));
}

Datum
gbt_float4_same(PG_FUNCTION_ARGS)
{
    float4KEY  *b1 = (float4KEY *) PG_GETARG_POINTER(0);
    float4KEY  *b2 = (float4KEY *) PG_GETARG_POINTER(1);
    bool       *result = (bool *) PG_GETARG_POINTER(2);

    *result = gbt_num_same((void *) b1, (void *) b2, &tinfo, fcinfo->flinfo);
    PG_RETURN_POINTER(result);
}
